Abstract Quantum mechanical method and apparatus for detecting and modulating electromagnetic radiation in a wavelength range of from about 5 to about 50 Mu . A potential difference (gate voltage) is impressed across a channel formed in a siliconsilicon dioxide MOS assembly. The magnitude of the gate voltage is used to adjust the energy levels of the electrons in the channel and when resonant photons are introduced into the channel there occurs photoresistance along the channel, the magnitude of which is a function of the number of resonant photons entering the channel. The photoresistive effects are the result of the interaction between the quantized electrons in the channel and photons in the radiation introduced into the channel. The device may be voltage-tunable over the wavelength range and may be used as a detector set to sense radiation of a given wavelength or as a multispectral rapid scanning device. When a gate voltage is used to maximize the photoresistive effect for radiation of a given wavelength, the radiation may be amplitude modulated by superimposing a small auxiliary ac gate voltage on the dc gate voltage to periodically reduce the photoresistive effect, thus alternately absorbing and transmitting radiation.
A quantum mechanical voltage-tunable electromagnetic radiation detector, comprising in combination a. a semiconducting silicon base member having at least one bevelled edge thereby to provide a surface normal to the direction at which radiation is introduced into said detector; b. a silicon dioxide layer on the surface of said base forming an interface therewith; c. charge carrier source and charge carrier drain means forming a channel at said interface; d. variable voltage applying means for impressing a gate voltage across said channel; e. radiation directing means, including said bevelled edge of said base member, adapted to introduce electromagnetic radiation into said channel in a manner to obtain a radiation component of electric field vector perpendicular to said channel; f. means to impress a potential difference along said channel; and g. means to measure the electrical resistance along said channel as a function of said gate voltage.
Claim 2
Dependent Claim
146 words
A quantum mechanical voltage-tunable electromagnetic radiation detector, comprising in combination a. a semiconducting silicon base member having at least one bevelled edge thereby to provide a surface normal to the direction at which radiation is introduced into said detector; b. a silicon dioxide layer on the surface of said base forming an interface therewith; c. charge carrier source and charge carrier drain means forming a channel at said interface; d. variable voltage applying means for impressing a gate voltage across said channel; e. radiation directing means, including said bevelled edge of said base member, adapted to introduce electromagnetic radiation into said channel in a manner to obtain a radiation component of electric field vector perpendicular to said channel; f. means to impress a potential difference along said channel; and g. means to measure the electrical resistance along said channel as a function of said gate voltage.
Claim 3
Dependent Claim
25 words
A voltage-tunable detector in accordance with claim 1 wherein said silicon base is p-type and said channel is characterized as being an electron inversion layer.
Claim 4
Dependent Claim
26 words
A voltage tunable detector in accordance with claim 1 wherein said silicon base is p-type and said channel is characterized as being a hole accumulation layer.
Claim 5
Dependent Claim
26 words
A voltage tunable detector in accordance with claim 1 wherein said silicon base is n-type and said channel is characterized as being a hole inversion layer.
Claim 6
Dependent Claim
25 words
A voltage-tunable detector in accordance with claim 1 wherein said silicon base is n-type and said channel is characterized as being an electron accumulation layer.
Claim 7
Dependent Claim
28 words
A voltage-tunable detector in accordance with claim 1 further characterized as being sensitive to electromagnetic radiation in the wavelength range of about 5 to about 50 Mu .